Equilibrium Reconstruction And Integration Of Efit With Diagnoses In J-TEXT Tokamak

Magnetic fittings is one of the basic subjects in operation of tokamak device. It can be used to get many discharge parameters of tokamak device which are difficult to be directly measured. And these parameters can provide an important reference for the operation of the device. In order to be able to be stable, efficient and reliable to reconstruct the equilibrium of plasma and the profiles of these parameters of J-TEXT device, this paper is on the basis of EFIT program to study the reconstruction of plasma equilibrium and the calculation of internal parameters in J-TEXT device.For the problem that the previous EFIT program used on the J-TEXT Tokamak is difficult to run stably, the theoretical basis of plasma equilibrium and the EFIT algorithm as one of the method for solving equilibrium reconstruction are studied in this paper. And then by combing the structure of previous EFIT program, the function of the main subroutine and the input parameters of the program are analyzed and optimized, which can improve the accuracy and stability of the EFIT program. The operation of original EFIT program is manual and cumbersome. In this paper, a set of interface and analysis programs combined with EFIT program by the MATLAB language is developed. This program structurally integrates four parts: measured data retrieval, input file generation, magnetic fittings, and visualization. Through optimizing calculation process on the whole, the above five parts of the program are integrated, and a GUI interface for the calculation is designed, which simplifies the operation process of the EFIT program, reduce the computational error caused by human factors and improve the efficiency and accuracy of the Magnetic fittings. For the problem that the size of the magnetic safety factor in the original EFIT program is given by experience, in this paper the automatic magnetic fitting calculation program is improved so that the automatic program can add the ECE, SXR and POLARIS diagnostic data as constraints to the calculation. And then, the size of the magnetic safety factor can be convenient to be confirmed by feedback calculation. As a result, the result of the equilibrium reconstruction is more accurate and the reliability of the magnetic fittings is improved to a certain extent.In this paper,for the partial deficiency of the EFIT program used on the J-TEXT device, a set of interface and analysis programs is developed and some interna diagnostic data is added as constraints to the calculation on the basis of deep study of the algorithm for solving equilibrium reconstruction. with these work carried out, not only are the stability and efficiency of the program for magnetic fittings improved, but also the reliability of results of Magnetic fittings is improved. Besides these work provide a strong support for the equilibrium reconstruction of J-TEXT device and has also certain reference value to the optimization of the programs for magnetic fittings on other devices.